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Mate Choice And Sexual Conflict In A Livebearing Fish, Julia C. Kasper

Master's Theses

Eavesdropping occurs when a receiver extracts information from an interaction without directly engaging with the signaler. Eavesdropping has been shown to be an effective way of evaluating the quality of potential mates and their abilities in male-male competition, without having to directly interact with them, thereby reducing energy costs and mating harassment. Girardinus metallicus is a livebearing poeciliid fish endemic to Cuba whose mating system is dominated by mating harassment in the form of sneak copulations, persistent displaying, and male-male aggression. G. metallicus has a male specific polymorphism in both melanin coloration and behavior. Males with melanin coloration are known …

Cellular Heat Responses Of Desert Mammals Promote Survival In Extreme Conditions, Janessa Montenegro

UNLV Theses, Dissertations, Professional Papers, and Capstones

Increasing temperatures with the potential for heat stress is among the future threats facing many mammals. Cellular mechanisms to maintain homeostasis in the face of heat stress likely differ across species based on naturally tolerated intracellular variability. In some mammals, the homeostatic set point in cells has a narrow range. Other species tolerate more varied intracellular conditions, including in temperature. Heat stress responses of cultured dermal fibroblasts from several mammals were compared to detect cell proliferation and cellular death (chapter 2). Cells from heat- tolerant species (13-lined ground squirrel, dromedary camel, round-tailed ground squirrel, and white-tailed antelope squirrel) were compared …

An Ecological Survey Of East Texas Salamanders Across The Camp Tyler Outdoor Field School In Smith County, Texas, Justin C. Hunt

Biology Theses

Amphibians are a unique class of organisms with a very long and storied evolutionary history of survival. Many modern amphibian clades occupy several vital ecological roles within their native freshwater environments. One of these roles, typically includes functioning as an ecological indicator species, whereby the presence of stable and diverse populations of many amphibian species, including salamanders, within a freshwater ecosystem have long been considered ecological indicators of good habitat quality and stable ecosystem health. Similarly, salamanders also function as important members of their local food webs and act as valuable mediators of complex trophic hierarchies to facilitate nutrient cycling …

Monitoring The Effects Of Poultry Waste On Fishes And Macroinvertebrates In The Sabine River, Karley R. Parker

Biology Theses

Freshwater is a vital resource that provides life and sustainability for almost all organisms on Earth. It is important to maintain its health and protect it from emerging pollutants that pose a threat to the organisms that use it. Pollution continues to threaten the well-being of the environment’s freshwater sources all around the world that could lead to damaging effects in the future. The Sabine River is a major freshwater resource in the east Texas and western Louisiana areas that provides a habitat for thousands of organisms as well as other domestic uses for humans. In 2019, a waste discharge …

The Third Domain Of T Cells In The Evolution Of Novel Immune Cell Types, Kimberly Anne Morrissey

Biology ETDs

ABSTRACT αβ and γδ T cells play an essential role in the adaptive immune response and are present in the majority of jawed vertebrates. The T cell receptor (TCR) structure and genetic organization have been generally stable throughout 400 million years of gnathostome evolution. However, the TCRδ chain has displayed degrees of plasticity unseen in other TCR isoforms. One such form appears to be a chimera of a TCR chain with an antibody-like binding domain, known as VHδ and has been found a wide array of vertebrates including cartilaginous fish, coelacanths, amphibians, tuataras, birds, crocodilians, and monotreme mammals. Another, more …

Investigating The Costs And Benefits Of A Nutritional Fungal Endosymbiont, Nolan L. Perryman

Biology ETDs

Research on insect symbiosis is dominated by insect–bacteria models, however, the role of fungal symbionts in insects is poorly understood. Fungi are de novo synthesizers of many essential nutrients, therefore, insect–fungal pairings can permit specialization on nutritionally deprived diets. Here, I address the costs and benefits of symbiosis using a system of beetle–fungal symbiosis. Specifically, I ask 1) when reared on a low-quality diet, does the beetle increase the number of viable symbionts to compensate for a heightened nutritional demand, and 2) Is the conferred fitness benefit of the symbiont only present in low-quality diets? When reared on low-quality diets, …

The Prevalence Of Diabetes In Juveniles, Tatyana Johnson

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Diabetes mellitus, simply known as diabetes, is a metabolic disorder that impacts how the body makes use of glucose or blood sugar. Glucose is the primary supply of energy for the body’s cells, which is controlled by insulin, a pancreatic hormone. Diabetes results in high blood glucose levels (hyperglycemia), which are caused by either insufficient insulin production by the pancreas or ineffective insulin utilization by the body (Dean & McEntyre, 2004). Although there are several types of diabetes, the two main types are type 1 and type 2. Type 1, also known as juvenile diabetes, is an inflammatory condition in …

Early Stage Or Curable Cancer Diagnoses In Minorities: A Journey Of Survivors, Lora Asberry

Master of Science in Integrative Biology Theses

Patients diagnosed with early-staged or curable forms of cancer experience physical, as well as, mental challenges associated with disease progression and treatment. Previous studies have demonstrated that minorities and underrepresented communities did not receive the same level of care in comparison to their non-minority counterparts. Previous studies have also demonstrated that health disparities among minorities affected their cancer journey. This study addressed: how medical disparities varied between minorities and non-minorities, the overall effects of the cancer diagnoses in minorities compared to non-minorities, whether these perspectives differed in male vs. female participants, and whether there were any possible communication barriers between …

Characterization Of Etoxazole Resistance In Tetranychus Urticae Populations Collected From Commercial Greenhouses & Fields In Ontario, Jeremy Spenler

Electronic Thesis and Dissertation Repository

In this investigation, etoxazole resistance was monitored in two spotted spider mite (TSSM) populations collected from commercial greenhouses in Ontario. The frequency of an etoxazole resistant, recessive target-site mutation, I1017F, in chitin synthase I (CHS1) was tracked within populations over the course of the study. Cytochrome P450 (P450) activity emerged as a possible alternative mechanism to resist etoxazole exposure in one population.

Using genetic crossing between highly resistant mite populations and a susceptible lab population, filial (F1) hybrid populations were created. The recessive I1017F target-site mutation was abolished in F1 hybrids highly susceptible to etoxazole, while elevated P450 …

Phylogeny And Taxonomy Of Genus Physaria In North America, Binoshi Hettihewa

Theses

Physaria is a genus of ~108 species belonging to family Brassicaceae that is predominantly distributed in Western North America, but one species occurs in Arctic Russia and Northern Canada and several species occur in South America. Regardless of the vast number of species in the genus, the genus lacks a well-resolved phylogeny representing many taxa, partially because phylogeny reconstruction is complicated by the fact that many species of Physaria vary in chromosome numbers and ploidy levels. In chapter 1, we review how polyploids are formed and become established and summarize what is known about variation in chromosome number and ploidy …

Phylogeographic History Of The Leaf-Eared Mouse, Phyllotis Xanthopygus Complex, Tabitha R. Mcfarland

Biology ETDs

Museum collections provide essential biodiversity sampling needed to understand the species limits, phylogeny, and biogeographic history of mammals, all key features of the foundation for comparative analyses in ecology and evolution. We add to this framework a diverse assemblage of species of leaf-eared mice (genus Phyllotis) in South America and then focus on the Phyllotis xanthopygus complex by combining available mitochondrial sequence (cytochrome b; cytb) data (351 GenBank samples) with 52 newly sequenced museum samples from the northern extent of this complex’s range (51 from Bolivia and 1 from northern Chile) to reconstruct evolutionary relationships using maximum …

Functional Analysis Of The Gamma-Aminobutyric Acid Type A Receptor Subunit Alpha-1 (Gabra1) Gene During Zebrafish Development., Nayeli Gabriela Reyes-Nava

Open Access Theses & Dissertations

The GABRA1 gene encodes for the alpha-1 (α1) subunit of the Gamma-Aminobutyric acid type A receptor (GABAAR), which are the primary modulators of synaptic inhibition in the central nervous system (CNS). Alpha-1 subunits are essential for maintaining the normal function of native receptors and contribute to over 60% of all GABAARs in the CNS. Remarkably, a broad spectrum of neurodevelopmental and epilepsy-associated disorders have been linked with mutations in the GABRA1 gene. However, the developmental, behavioral, and molecular mechanisms underlying GABRA1-associated epileptic disorders remain to be fully understood. Hence, the overarching goal of this dissertation is to investigate the behavioral …

Cadmium And Salinity Stressor Antagonism On Vallisneria Neotropicalis, Christopher P. Mikolaitis

<strong> Theses and Dissertations </strong>

Submerged macrophytes form the foundation of freshwater ecosystems. These organisms are sessile and are very susceptible to shifts in their environment. Heavy metals are of particular concern as they can be sequestered indefinitely in sediments and are readily taken up by rooted vegetation. In the presence of saltwater intrusions, these metals can interact with salt ions potentially changing their availability to submerged vegetation. In this study a freshwater macrophyte, Vallisneria neotropicalis, was used as a test species for interactive effects between Cd, a non-essential heavy metal, and salt stress. The metrics used to establish the individual as well as …

Sympatric Soil Microbe Interactions Between Streptomyces And Fusarium Isolates, Lehren A. Olk-Szost

All NMU Master's Theses

Interkingdom interactions between soil bacteria and fungi may play a critical role in occurrence of disease suppressive soils, yet our understanding of these interactions remains limited. Streptomyces are well-known producers of antimicrobial compounds important to medicine and agriculture. Production of these secondary metabolites is often mediated by quorum sensing. Most Streptomyces research occurs in single species experiments, yet new metabolites have been discovered in interspecies co-culture experiments. Interspecies, intergenic, and interkingdom co-culture research will likely reveal many valuable compounds, and strengthen our understanding of complex ecological interactions in soil microbiomes. Interactions between sympatric Streptomyces and Fusarium isolates from disease suppressive …

Improving Cold Tolerance Of Asian Rice Through Plant Growth Promoting Bacteria And Rice Gene Manipulation: Mechanisms Of Pseudomonas Mosselli And Osmads27, Nasim Maghboli Balasjin

Dissertations (1934 -)

It is estimated that by the year 2050, the human population will extend to 9.7 billion and therefore the demand for food will increase. It is important to find ways to maintain production of critical crops, like rice, to match the demand. Climate change affects crop productivity as it is the reason for extreme warm or cold weather fluctuations. Asian rice (Oryza sativa L.) generally is grown in tropical and subtropical regions and thus, is sensitive to cold temperatures. This study hypothesized two strategies could improve growth and cold tolerance of rice plants: (1) use of plant growth promoting bacteria …

An Evolutionary Comparative Study Of Congenital Stationary Night Blindness-Associated Trpm1 Genetic Variants Of Uncertain Significance In Horses And Humans Utilizing Caenorhabditis Elegans, Gabrielle Davis

Theses

Congenital stationary night blindness (CSNB) is a heterogeneous collection of genetic diseases affecting the eyes and vision in horses and humans. Current research has implicated several genetic mutations impacting different genes involved in phototransduction and signal transmission, including TRPM1. In horses, genetic mutations in TRPM1 also result in a leopard spotting pattern or leopard complex. The goal of this study is to examine the potential impact of CSNB associated TRPM1 missense variants of uncertain significance (VUS). Previous research in Caenorhabditis elegans have revealed an orthologous TRPM1 gene known as gon-2 that allows for comparative studies. The evolutionary relationship of …

Comparative Analysis Of Soil Properties, Microbial Community Composition, And Yield Responses To Cover Crops In Different Ecoregions Of South Texas, Daphne Zapsas

Theses and Dissertations

Comprehensive understanding of soil properties, their interdependencies, and the effects of management practices is crucial for designing sustainable agricultural strategies. By adopting site-specific and need-based practices that enhance soil health, farmers can optimize crop growth, increase yield, and contribute to long-term environmental sustainability. Cover crops have been recognized for enhancing soil fertility, promoting microbial activity, and increasing organic matter content. However, while their effectiveness is well documented in temperate regions with readily available water, their impact in water limited systems in subtropical regions remains mixed. The aim of this study is to assess soil conditions in four different farms across …

Soil Moisture Dynamics In Cover Cropping Systems: From Local To Global Scales, Manish Gautam

Theses and Dissertations

Cover cropping systems, which have gained recognition for their ability to enhance soil health and promote sustainability are also associated with potential risks related with declining soil moisture and pose a dilemma for farmers considering the adoption of cover crops in water deficit semi-arid settings worldwide. To address this pressing issue, we conducted a participatory cover cropping trial in the Lower Rio Grande Valley (LRGV) region, encompassing four different farms and supplemented this experiment with a meta-analysis to answer our soil moisture and climate parameters and quantify the impact of cover crops on soil moisture levels. The findings revealed that …

Modulation Of Eif2Α Signaling And The Integrated Stress Response By Targeted Therapeutic Attenuation Of Pkr Activity Contributes To Protection Of Dyt-Prkra Cells From Apoptosis, Kenneth L. Frederick

Theses and Dissertations

Luteolin is a natural flavonoid present in vegetables, fruits, and medicinal herbs that possesses anti-oxidative, anti-cancer, and anti-inflammatory properties. In this study, we investigated the effect of luteolin on the integrated stress response (ISR), which is an evolutionarily conserved intracellular signaling network essential for adapting to environmental stresses to maintain healthy cells. Dysregulated ISR is involved in the etiology of many human diseases including the movement disorder DYT-PRKRA which is caused by mutations in the PRKRA gene. PRKRA encodes for PACT, the protein activator of interferon-induced, double-stranded RNA (dsRNA)-activated protein kinase PKR.PACT-mediated PKR activation regulates the …

The Effects Of Variations In Light And Nutrient Availability On Phytoplankton And Zooplankton, Jake Anthony Swanson

Theses and Dissertations

Aquatic ecosystems experience a wide range of variation in resource availability; two of the resources that are most essential to phytoplankton and zooplankton are light and nutrients. Light can vary in both its color and intensity; these variations can directly impact phytoplankton by altering the amount and color of light available for photosynthesis. Nutrient variability, particularly increases in nutrient levels, also alter phytoplankton communities by favoring the growth of certain taxa such as cyanobacteria.

To understand whether phytoplankton respond differently to changes in light availability I investigated whether the diversification of cryptophytes, phytoplankton with diverse light-capturing pigments, showed evidence of …

Diversity, Function, And Phenotypic Plasticity Of Cryptophyte Phycobiliproteins, Kristiaän Merritt

Theses and Dissertations

Cryptophytes are a group of unicellular eukaryotic algae that can be found in a wide range of underwater habitats. Part of their ecological success can be attributed to their diverse array of cryptophyte phycobiliproteins (Cr-PBPs), a pigment class that captures wavelengths of light that are poorly absorbed by chlorophylls. Cryptophytes gained photosynthesis via secondary endosymbiosis in which their ancestor engulfed a red algal endosymbiont. Following endosymbiosis, they deconstructed the red algal photosynthetic machinery to form the Cr-PBP. Since then, the Cr-PBPs have diversified into at least 9 spectrally distinct forms. I investigated the diversity of Cr-PBP light absorption across 76 …

Influence Of Woody Vegetation Composition And Structure On Fuels And Prescribed Fire In Mountain Longleaf Restoration, Collin J. Anderson

Master of Science in Integrative Biology Theses

Longleaf pine (LLP) ecosystems have experienced a widespread ecological state shift largely due to fire exclusion which has allowed mesophytes, i.e., shade-tolerant, often fire-sensitive species to encroach, reducing flammability and biodiversity through a process known as “mesophication.” Although prescribed fire is commonly used to reverse mesophication, fire behavior, and thus prescribed fire utility for this purpose, is poorly characterized in mixed pine-hardwood stands with mesophyte encroachment. This study aimed to identify mechanisms by which tree composition, structure, and fuels contribute to fire behavior, focusing on the understudied mountain longleaf pine (MLLP) ecoregion in northwest Georgia. I hypothesized that woody vegetation …

Variation In Salamander Life History And Community Composition Across An Urban Gradient In Atlanta, Georgia, Usa, Leah Rittenburg

Master of Science in Integrative Biology Theses

Urbanization threatens to alter stream systems in watersheds in the eastern United States. These highly disturbed systems may result in many local extirpations of sensitive salamander species. One group of organisms that often persists in urban streams is the Eurycea bislineata (Two-lined Salamander) species complex. Many aspects of Two-lined Salamander life history are linked to environmental factors, particularly stream temperature, prey abundance, and stream hydrology. Urbanization threatens to alter these environmental factors, potentially influencing Two-lined Salamander life history. At 14 sites spanning an urban gradient in Atlanta, GA, I investigated the variation in life history and phenology in the Southern …

Resource Recovery From Crew Metabolic Wastes In Lunar And Martian Habitats: Reuse Of Effluent From An Anaerobic Membrane Bioreactor Treating Fecal Organic Matter As Fertilizer Source For Plants, Alexandra A. Smith

USF Tampa Graduate Theses and Dissertations

As humans set their sights on exploration of the Moon and Mars human focused challenges like providing potable water, supplying nutritious food to the astronaut crew, and managing their waste present themselves. There are no readily available resources on the Moon and Mars, therefore nothing should be considered unusable including the organic wastes (i.e., feces and urine) produced by the crew. Fecal matter is not currently recycled and is treated as solid waste. After collection, it is discarded out of the International Space Station where it is incinerated upon re-entry. This approach will not work on the Moon’s surface. There …

The Manhattant: Identification, Natural History, And Nutritional Ecology Of A Recently Introduced Pest In New York City, Lasius Emarginatus (Hymenoptera: Formicidae), Samantha Kennett

Master of Science in Integrative Biology Theses

New York City is one of the oldest and largest cities in North America, and it is a center for global trade and shipping. As such, it has also been the site of introduction for some of North America’s most damaging invasive pests, from chestnut blight to the Asian long-horned beetle. Despite these cautionary examples, there has been no formal research on a newly introduced ant species that was tentatively identified as a European ant species, Lasius cf. emarginatus. Since its discovery in 2011, L. cf. emarginatus has become among the most common urban ant species in New York …

Examination Of Microplastics And Organic Contaminants In Tampa Bay’S Eastern Oyster (Crassostrea Virginica) Through Visual And Chemical Analysis, Andrea Murray

USF Tampa Graduate Theses and Dissertations

Microplastic pollution is an increasingly alarming concern with widespread global distribution in aquatic environments. Filter feeding organisms such as bivalves, have a heightened risk of microplastic ingestion through free floating particulates in the water. This can lead to bioaccumulation moving up through trophic levels to apex predators and humans. Spatial and temporal differences in microplastic abundance were evaluated in the Eastern Oyster, Crassostrea virginica, at six sites within Tampa Bay. Oyster tissue was digested using 30% hydrogen peroxide (H2O2) and microplastics were quantified using Nile Red dye and fluorescent particle excitement. A total of 3025 microplastics were found throughout six …

Genetic Population Structure And Effective Number Of Breeders In Systems Across The Range Of The Gulf Sturgeon, Jacob Zona

Master's Theses

Gulf sturgeon (Acipenser oxyicnhus desotoi) are a large, anadromous fish belonging to an ancient lineage that diverged as early as 400 MYA. Overfishing for meat and caviar during the early 1900’s reduced their range and abundance and continued habitat destruction and mortality have limited their ability to recover, leading to their listing under the Endangered Species Act. This study uses genetic techniques to determine the effective number of breeders for multiple spawning groups of Gulf sturgeon in river systems across their range to set a baseline for tracking reproductive success of the species. Accompanying genetic information relevant to …

Cytotoxic Activity Of Salvia Officinalis Extract Mediated By The Inhibition Of Jak2 In Breast Cancer, Salma Alawadi Dawood

Theses and Dissertations

Background: Breast cancer is the most common type of invasive cancer in women in their forties and fifties. Recent evidence suggests that JAK2/STAT3 signaling is constitutively active in breast cancer. Previous studies suggest that plant extracts, including Salvia Officinalis, have strong cytotoxic effects on breast cancer cells. The differential expression of miRNAs is also strongly linked to cancer development.

Aim: In the current study, we hypothesize that S. Officinalis extract suppresses JAK2 expression and has strong anticancer potential in MCF7 breast cancer cell lines.

Methods: GC-MS analysis showed the presence of flavonoids in dried leaf of …

Pleurotus Spp. As Agents Of Mycoremediation: A Review, Colin Innes

University Honors Theses

Elemental and molecular contaminants of anthropogenic origin represent an increasing threat to virtually all terrestrial and aquatic environments as well as their surrounding atmosphere. The decontamination and restoration of these environments pose a significant and expensive challenge. Although chemical treatment or physical removal of contaminated substrates often is the most direct response to eliminate contaminants, due to the complexity and sensitivity of many natural systems, technologies involving biological remediation can provide viable alternatives. While plant, bacterial, and fungal organisms have the abilities to accumulate or to metabolize toxic compounds, fungal organisms are uniquely suited to do so. Their fast growth …

Evaluating Sport Fish Use Of Natural And Introduced Habitats In Nebraska Reservoirs, William Michael Schriener

Biology Theses, Dissertations, and Student Creative Activity

Reservoirs are often limited in habitat, and many habitats can be lost through natural decomposition, sedimentation, and as reservoir water elevations changes as reservoirs age. Aquatic managers recognize the importance of maintaining habitat in reservoirs and habitat augmentation projects are common. However, this study was designed to improve understanding surrounding the placement and use of added structures by exploring the following objectives: 1) Quantify the availability of different habitats and how that availability changes under different reservoir elevations; 2) Compare fish assemblages around different habitats; 3) Compare sportfish relative abundance and total lengths between habitats; of Harlan County Reservoir, and …